Method and device for determining input information

ABSTRACT

The present application provides methods and devices for determining input information, and generally relates to the field of wearable devices. A method disclosed herein comprises: in response to a first part of a body of a user executing an action, acquiring target blood-flow information about the first part or a second part that corresponds to the first part; and determining input information according to the target blood-flow information and reference information. According to the methods and devices, the body of the user is used as an input interface, thus cause an interaction area to be increased, which helps to improve input efficiency and user experience.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a National Phase Application of InternationalApplication No. PCT/CN2016/070378, filed on Jan. 7, 2016, which claimspriority to and benefit of Chinese Patent Application No.201510070064.3, filed on Feb. 10, 2015, and entitled “Method and Devicefor Determining Input Information”. Both of the above-referencedapplications are hereby incorporated into the present application byreference herein in their entirety.

TECHNICAL FIELD

The present application generally relates to the field of wearabledevices, and in particular, to methods and devices for determining inputinformation.

BACKGROUND

With the popularity of electronic devices, people use and controlelectronic devices to help with work, study, and leisure almost everyday. Enabling a user to conveniently and quickly control an electronicdevice has been a long-pursued goal of manufacturers of electronicdevices.

A wearable device (such as a smart watch, smart gloves, and smartaccessories) among electronic devices usually has characteristics suchas being attached to users, compact, and low energy consumption. Thesecharacteristics determine that many wearable devices have a small inputarea and low input capability.

SUMMARY

An objective of the present application is to provide methods anddevices for determining input information.

According to an aspect of at least one embodiment of the presentapplication, a method for determining input information is provided. Themethod comprises:

in response to a first part of a body of a user executing an action,acquiring target PPG information about the first part or a second partthat corresponds to the first part; and

determining input information according to the target PPG informationand reference information.

According to another aspect of at least one embodiment of the presentapplication, a device for determining input information is provided. Thedevice comprises:

an acquiring module, configured to acquire target PPG information abouta first part of a body of a user or a second part that corresponds tothe first part, in response to the first part executing an action; and

a determining module, configured to determine input informationaccording to the target PPG information and reference information.

According to another aspect of at least one embodiment of the presentapplication, a method for determining input information is provided. Themethod comprises:

in response to a first part of a body of a user executing an action,acquiring target blood-flow information about the first part or a secondpart that corresponds to the first part; and

determining input information according to the target blood-flowinformation and reference information.

According to another aspect of at least one embodiment of the presentapplication, a device for determining input information is provided. Thedevice comprises:

an acquiring module, configured to acquire target blood-flow informationabout a first part of a body of a user or a second part that correspondsto the first part, in response to the first part executing an action;and

a determining module, configured to determine input informationaccording to the target blood-flow information and referenceinformation.

According to the methods and devices for determining input informationin some embodiments of the present application, in response to a firstpart of a body of a user executing an action, target blood-flowinformation about the first part or a second part that corresponds tothe first part is acquired; and input information is determinedaccording to the target blood-flow information and referenceinformation, thereby affecting the target blood-flow information bymeans of a body action of a user, and moreover, the input information isdetermined according to the target blood-flow information. The body ofthe user is used as an input interface, to cause an interaction area tobe increased, which helps to improve input efficiency and userexperience.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of a method for determining input informationaccording to an embodiment of the present application;

FIG. 2 is a schematic diagram of detecting PPG information according toan implementation manner of the present application;

FIG. 3 is a schematic diagram of PPG information detected in a normalcase;

FIG. 4 is a schematic diagram of LDF information detected in a normalcase;

FIG. 5 is a detailed flowchart of step S140 a according to animplementation manner of the present application;

FIG. 6 is a detailed flowchart of step S141 a according to animplementation manner of the present application;

FIG. 7 is a schematic diagram of target PPG information detected in acase in which a middle finger clicks according to an implementationmanner of the present application;

FIG. 8 is a schematic diagram of target PPG information detected in acase in which a fist is made according to an implementation manner ofthe present application;

FIG. 9 is a detailed flowchart of step S1411 a according to animplementation manner of the present application;

FIG. 10 is a schematic diagram of target PPG information detected in acase in which an index finger clicks according to an implementationmanner of the present application;

FIG. 11 is a schematic diagram of target PPG information detected in acase in which an index finger double-clicks according to animplementation manner of the present application;

FIG. 12 is a detailed flowchart of step S1412 a according to animplementation manner of the present application;

FIG. 13 is a detailed flowchart of the step S140 a according to animplementation manner of the present application;

FIG. 14 is a detailed flowchart of the step S140 b according to animplementation manner of the present application;

FIG. 15 is a schematic diagram of reference-velocity-related informationaccording to an implementation manner of the present application;

FIG. 16 is a schematic diagram of target-velocity-related information ina case in which an index finger clicks according to an implementationmanner of the present application;

FIG. 17 is a schematic diagram of target-velocity-related information ina case in which a middle finger clicks according to an implementationmanner of the present application;

FIG. 18 is a schematic diagram of target-velocity-related information ina case in which an index finger double-clicks according to animplementation manner of the present application;

FIG. 19 is a detailed flowchart of the step S140 b according to animplementation manner of the present application;

FIG. 20 is a schematic structural diagram of modules of a device fordetermining input information according to an embodiment of the presentapplication;

FIG. 21 is a schematic structural diagram of modules of the determiningmodule according to an implementation manner of the present application;

FIG. 22 is a schematic structural diagram of modules of the firstdetermining submodule according to an implementation manner of thepresent application;

FIG. 23 is a schematic structural diagram of modules of the firstdetermining unit according to an implementation manner of the presentapplication;

FIG. 24 is a schematic structural diagram of modules of the seconddetermining unit according to an implementation manner of the presentapplication;

FIG. 25 is a schematic structural diagram of modules of the determiningmodule according to an implementation manner of the present application;

FIG. 26 is a schematic structural diagram of modules of the determiningmodule according to an implementation manner of the present application;

FIG. 27 is a schematic structural diagram of modules of the firstdetermining submodule according to an implementation manner of thepresent application;

FIG. 28 is a schematic structural diagram of modules of the second unitaccording to an implementation manner of the present application;

FIG. 29 is a schematic structural diagram of modules of the firstdetermining subunit according to an implementation manner of the presentapplication;

FIG. 30 is a schematic structural diagram of modules of the seconddetermining subunit according to an implementation manner of the presentapplication;

FIG. 31 is a schematic structural diagram of modules of the determiningmodule according to an implementation manner of the present application;and

FIG. 32 is a schematic structural diagram of hardware of a device fordetermining input information according to an implementation manner ofthe present application.

DETAILED DESCRIPTION

The following further describes the specific implementation manners ofthe present application in detail with reference to the accompanyingdrawings and embodiments. The following embodiments are used toillustrate the present application, but are not intended to limit thescope of the present application.

It is understood by a person skilled in the art that, in the embodimentsof the present application, sequence numbers of the following processesdo not mean execution sequences in various embodiments of the presentinvention. The execution sequences of the processes should be determinedaccording to functions and internal logic of the processes, and shouldnot be construed as any limitation on the implementation processes ofthe embodiments of the present invention.

It is found by the inventor in a research process that, if a body of auser is in a motion state, acquired blood-flow information comprises anoise produced by the motion. Generally, people will attempt toeliminate the noise, so as to improve the accuracy of the acquiredblood-flow information.

Meanwhile, it is found by the inventor that, motions of different partsof the body of the user or different motions of a same part of the bodyof the user produce different noises, to cause the acquired blood-flowinformation to have different waveform features. Based on this, it maybe reasonably inferred which part performs what action according to theobtained blood-flow information, and further, corresponding inputinformation may be determined. The blood-flow information may be PPG(photoelectric plethysmography) information, and may also be Dopplermeasurement information.

FIG. 1 is a flowchart of a method for determining input informationaccording to an embodiment of the present application. The method may beimplemented by, for example, a device for determining input information.As shown in FIG. 1, the method comprises:

S120: In response to a first part of a body of a user executing anaction, acquire target blood-flow information about the first part or asecond part that corresponds to the first part.

S140: Determine input information according to the target blood-flowinformation and reference information.

According to the method, in response to a first part of a body of a userexecuting an action, target blood-flow information about the first partor a second part that corresponds to the first part is acquired; andinput information is determined according to the target blood-flowinformation and reference information, thereby affecting the targetblood-flow information by means of a body action of a user, andmoreover, the input information is determined according to the targetblood-flow information. The body of the user is used as an inputinterface, to cause an interaction area to be increased, which helps toimprove input efficiency and user experience.

The following describes functions of the steps S120 and S140 in detailwith reference to the specific implementation manners.

S120: In response to a first part of a body of a user executing anaction, acquire target blood-flow information about the first part or asecond part that corresponds to the first part.

The first part, that is, an action part, for example, may be a finger, apalm, a wrist, a neck, a foot, a leg, and the like of a user. Inaddition to being used as the action part, the first part may also beused as an acquisition part for target blood-flow information at thesame time, for example, in a case in which an acquiring sensor for thetarget blood-flow information is a smart bracelet, the wrist may be usedas the action part and the acquisition part simultaneously.

The second part is another optional acquisition part for the targetblood-flow information. Moreover, the second part is a part adjacent tothe first part. That is, a distance between the first part and thesecond part should be less than a distance threshold, for example, thedistance is less than 0.1 m. Moreover, it is found by the inventor inthe research process that, a shorter distance between the first part andthe second part leads to a smaller error of the method. Generally, thefirst part and the second part are located at a same limb of the user.For example, in a case in which a finger is used as the action part, awrist on the same limb may be used as an acquisition part.

The actions may be some common actions in daily life, such as, a fingerclicks, a hand makes a fist, and a palm is stretched out, and may alsobe some training actions, such as a finger double-clicks fast.

As described above, the blood-flow information may be PPG information orDoppler measurement information. Correspondingly, the target blood-flowinformation may be target PPG information or target Doppler measurementinformation.

FIG. 2 is a schematic diagram of acquiring PPG information about a humanbody. The principle thereof is that a light receiving portion detectsthe intensity of reflected light after light emitted by a light emittingportion is reflected by a finger tip. Because blood has a lightabsorption property, the intensity of the reflected light changes with achange in a flow volume of blood that flows through the finger tipwithin a unit time. By measuring a cycle of the change of the reflectedlight, the PPG information may be obtained, and further, informationsuch as a heart rate may be obtained by calculation. Because hemoglobinin blood has better absorption effect on green light, generally, agreen-light LED may be used as the light emitting portion. In a normalcase, a waveform diagram of PPG information as shown in FIG. 3 may beobtained by means of detection.

The Doppler measurement information may be an LDF (Laser DopplerFlowmetry), an LDV (Laser Doppler Velocimety), and an ultrasonic Dopplerfrequency shift. The implementation principles thereof are similar. LDFinformation is used as an example, and the acquiring principle thereofis that a laser signal sent by a light emitting unit is detected by aphotoelectric sensor after reflection by erythrocyte, and by analyzing aDoppler frequency shift of an electrical signal output by thephotoelectric sensor, a flow speed and a blood-flow volume of blood maybe measured. An optical blood flow sensor based on the LDF principle maybe used to measure a heart rate and the like. In a normal case, awaveform diagram of LDF information as shown in FIG. 4 may be obtainedby means of detection.

S140: Determine input information according to the target blood-flowinformation and reference information.

a) In an implementation manner, the target blood-flow information istarget PPG information. Correspondingly, the step S140 is further asfollows:

S140 a: Determine input information according to the target PPGinformation and reference information.

In an implementation manner, a first correspondence between the targetPPG information and the input information may be directly established,and therefore the input information may be directly determined accordingto the target PPG information in combination with the referenceinformation.

At the same time, it is understood by a person skilled in the art that,there is further bridge information between the target PPG informationand the input information, that is, the first part and/or the action.That is, among the target PPG information, the first part and/or theaction, and the input information, there is a second correspondence.

Therefore, referring to FIG. 5, in an implementation manner, the stepS140 a may comprise:

S141 a: Determine the first part and/or the action according to thetarget PPG information and the reference information.

S142 a: Determine the input information according to the first partand/or the action.

It is understood by a person skilled in the art that, it may becompletely unnecessary for a device to understand the first part and/orthe action, that is, the device may perform processing completely basedon the first correspondence. However, for clearness, the secondcorrespondence is described in the present application. Because theprinciples of the first correspondence and the second correspondence arethe same, the first correspondence is not respectively described indetail herein again.

Referring to FIG. 6, in an implementation manner, the step S141 a mayfurther comprise:

S1411 a: Determine target difference information according to the targetPPG information and the reference information.

S1412 a: Determine the first part and/or the action at least accordingto the target difference information.

In an implementation manner, in the step S1411 a, the referenceinformation may be a first threshold. The first threshold may be setaccording to PPG information acquired, in a case in which the first partdoes not execute the action, that is, the first part remains static,from an acquisition part of the target PPG information (PPG informationacquired in a normal case for short below), for example, the firstthreshold is set to a minimum amplitude value of PPG informationacquired in a normal case, or a maximum amplitude value of PPGinformation acquired in a normal case.

The target difference information is a part of the target PPGinformation, and the action causes the part of the information to beobviously different from the PPG information acquired in a normal case.For example, in a case in which a middle finger clicks, an obtainedwaveform of the target PPG information is as shown in FIG. 7, where thepart of the waveform that is within the circle, is obviously differentfrom the waveform outside the circle. A part, which is within thecircle, of the waveform is a waveform corresponding to the targetdifference information. The waveform is a waveform formed due to achange in a normal PPG waveform, which is caused by a click performed bythe middle finger. It may be seen that, a minimum amplitude value of thepart, which is within the circle, of the waveform is obviously lowerthan an amplitude value of the PPG information acquired in a normalcase.

Therefore, in an implementation manner, the step S1411 a may further beas follows:

S1411 a′: Compare an amplitude value that is in the target PPGinformation and a value of the reference information, and determine thetarget difference information according to a comparison result.

Specifically, in a case in which the reference information is a minimumamplitude value of PPG information acquired in a normal case, a part,whose amplitude value is less than the value of the referenceinformation, of the target PPG information may be determined as thetarget difference information. Certainly, in a case in which thereference information is a maximum amplitude value of PPG informationacquired in a normal case, a part, whose amplitude value is greater thanthe value of the reference information, of the target PPG informationmay be determined as the target difference information. FIG. 8 is usedas an example. FIG. 8 shows a waveform of target PPG informationobtained at a wrist in a case in which a fist is made, where thewaveform within a circle formed of a solid line is obviously differentfrom the waveform outside the circle formed of the solid line. Thewaveform within the circle formed of the solid line is a waveformcorresponding to the target difference information, and the waveform isa waveform formed due to a change in a normal PPG waveform caused bymaking of a fist. It may be seen that, a maximum amplitude value of thewaveform within the circle formed of the solid line is obviously higherthan an amplitude value of the PPG information acquired in a normalcase.

It is understood by a person skilled in the art that, for the target PPGinformation in FIG. 8, target difference information, which is obtainedafter the target PPG information is processed according to the foregoingstep S1411 a′, may be only waveforms within two circles formed of dottedlines, that is, an entire waveform within a circle formed of a solidline may not be obtained. However, the waveforms within the two circlesformed of dotted lines and other information such as time may assist inrecognizing the action and the action part.

In another implementation manner, in the step S1411 a, the referenceinformation may be reference PPG information acquired from anacquisition part of the target PPG information in a case in which thefirst part does not execute the action, that is, the referenceinformation is PPG information acquired in a normal case. A waveform ofthe reference PPG information may be as shown in FIG. 3. The waveformmay be acquired in advance.

Correspondingly, referring to FIG. 9, in an implementation manner, thestep S1411 a may comprise:

S14111 a″: Divide the target PPG information into multiple pieces of subtarget PPG information according to a cycle.

S14112 a″: Respectively perform a cross-correlation calculation on themultiple pieces of sub target PPG information and the referenceinformation, and determine the target difference information accordingto a calculation result.

The waveform shown in FIG. 7 is still used as an example. In the stepS14111 a″, the waveform shown in FIG. 7 may be divided into C1, C2, C3,C4, and C5 by taking two adjacent wave crests as a cycle. There are fivesubwaveforms in total. The five subwaveforms are corresponding to fivepieces of sub target PPG information. A waveform at edges may beignored. This is because some extra pieces of PPG information may beacquired during acquiring of the target PPG information.

In the step S14112 a″, the reference information may be a PPG waveformbetween two wave crests, which is acquired in a normal case. After across-correlation calculation is respectively performed on the fivepieces of sub target PPG information and the reference information, itmay be found that, a result of a cross-correlation calculation on thereference information and C2 is obviously less than results ofcross-correlation calculations on the reference information and theother pieces of sub target PPG information. According to this, it may bedetermined that PPG information corresponding to C2 is the targetdifference information.

In an actual application, results of cross-correlation calculations ofthe reference information and each piece of sub target PPG informationmay be compared with a threshold, and if a result is less than thethreshold, it is determined that a piece of corresponding sub target PPGinformation is target difference information. The threshold may be, forexample, set to 80% of a result of a cross-correlation calculation ofthe reference information with itself.

It is understood by a person skilled in the art that, the foregoing twomanners for determining the target difference information may further beused together, to improve accuracy and efficiency.

In an implementation manner, the step S1412 a may further comprise:

S1412 a′: Determine the action according to the number of wave troughsor wave crests comprised in the target difference information.

The number of wave troughs or wave crests comprised in the targetdifference information is the same as the number of times that theaction is executed. As shown in FIG. 7, in a case in which a middlefinger clicks, the corresponding number of wave troughs is 1. As shownin FIG. 8, in a case in which a fist is made once, the correspondingnumber of wave troughs or wave crests is 1. In addition, FIG. 10 is awaveform of target PPG information, which is obtained in a case in whichan index finger clicks. The waveform within a circle is corresponding tothe target difference information, and the corresponding number of wavetroughs or wave crests of the target difference information is also 1.FIG. 11 is a waveform of target PPG information, which is obtained in acase in which an index finger double-clicks. The waveform within acircle is corresponding to the target difference information. It may beseen that, in this case, the number of wave troughs or wave crestscomprised in the target difference information is 2.

In another implementation manner, the step S1412 a may further comprise:

S1412 a″: Determine the action according to a cycle corresponding to thetarget difference information.

The cycle corresponding to the target difference information iscorresponding to a cycle in which the first part executes the action.That is, the longer the first part executes the action each time, thelonger the cycle of the target difference information is. Therefore, thecycle corresponding to the target difference information may reflect anexecution speed of the action, and therefore the action may bedetermined. For example, the first part is a foot. If a cycle of anaction of raising and putting down the foot is 0.3 s, it may bedetermined that a corresponding action is walking; and if a cycle of anaction of raising and putting down the foot is 0.03 s, it may bedetermined that a corresponding action is running. Certainly, in a casein which the first part is a hand, it may also be determined whether auser walks or runs according to a cycle of forward and backward swingingof the hand.

In another implementation manner, referring to FIG. 12, the step S1412 amay further comprise:

S14121 a: respectively calculate the similarity between a waveform ofthe target difference information and at least one known waveform, anddetermine a target known waveform according to a calculation result.

S14122 a: Determine the first part and/or the action according to thetarget known waveform.

The at least one known waveform may be a set of multiple known waveformsand may be obtained by pre-training, for example, the user makes thefirst part execute different actions in advance and correspondinglyacquires waveforms of corresponding target difference information as theknown waveforms. Therefore, correspondences among the first part, theaction, and the known waveform may be established. The correspondencesmay be as shown in Table 1.

TABLE 1 First part Action Known waveform Index finger Click A Indexfinger Double-click B Middle finger Click C Hand Make a fist D Hand OpenE

In an actual application, the similarity of a waveform of the targetdifference information, which is acquired in the step S14121 a and eachknown waveform in the set may be respectively calculated, and then aknown waveform of the highest similarity is selected as the target knownwaveform. Further, in the step S14122 a, the first part and/or theaction may be determined according to the target known waveform.

A first row in Table 1 is used as an example. It is assumed that awaveform of the target difference information is the waveform within acircle as shown in FIG. 10, and it may be obtained by calculation thatthe waveform of the target difference information is most similar to aknown waveform A, and therefore it may be determined that the targetknown waveform is the known waveform A, and it may further be determinedthat the first part is an index finger, and an action is click.

In the step S142 a, the input information is determined according to thefirst part and/or the action.

Correspondences between the first part and/or the action and the inputinformation may be predetermined, and the correspondences may be asshown in FIG. 2. A second row is used as an example. It is assumed thata smart bracelet is in communication with smart glasses, the smartbracelet acquires an action instruction of a user and controls the smartglasses, and in a case in which the smart bracelet recognizes an actionthat an index finger double-clicks, the smart bracelet may control thesmart glasses to enable an APP currently presented to the user, forexample, enable a camera function. A correspondence table as shown inTable 2 may be pre-stored in a wearable device, such as a smartbracelet, and moreover, such a correspondence table may be provided inan operating instruction of the wearable device, so as to instruct andtrain a user to perform corresponding command inputting by means of anaction similar to an action in Table 2.

TABLE 2 First part Action Input information Index finger Click Selectcommand Index finger Double-click Open command Middle finger Click Menucommand Hand Make a fist Zoom-out command Hand Open Zoom-in command

In addition, referring to FIG. 13, in another implementation manner, thestep S140 a may comprise:

S141 a′: Determine a signal feature of the target PPG information.

S142 a′: Determine the input information according to the signal featureand the reference information.

In the step S141 a′, the signal feature of the target PPG informationcomprises at least one of a fingerprint, an average value, and adifference of the target PPG information. The fingerprint is formed ofat least one of an amplitude, a phase, and a spectrum of the target PPGinformation; the average value is an average value of at least one ofthe amplitude, the phase, and the spectrum of the target PPGinformation; and the difference is a difference of at least one of theamplitude, the phase, and the spectrum of the target PPG information.

In the step S142 a′, the reference information may be a reference signalfeature obtained by pre-training, for example, in a training stage,corresponding actions may be executed according to Table 2, andcorrespondingly, signal features of corresponding PPG information may beacquired as the reference information. In a specific application, thesimilarities between the signal feature of the target PPG informationand multiple pieces of reference information may be obtained bycalculation, and input information corresponding to one piece ofreference information having the highest similarity is used as the inputinformation.

b) In another implementation manner, the target blood-flow informationis target Doppler measurement information. Correspondingly, the stepS140 is further as follows:

S140 b: Determine input information according to the target Dopplermeasurement information and reference information.

The target Doppler measurement information may be, such as, an LDF(Laser Doppler Flowmetry), an LDV (Laser Doppler Velocimety), and anultrasonic Doppler frequency shift.

Referring to FIG. 14, in an implementation manner, the step S140 b maycomprise:

S141 b: Determine the first part and/or the action according to thetarget Doppler measurement information and the reference information.

S142 b: Determine the input information according to the first partand/or the action.

In an implementation manner, the step S141 b may further comprise:

S1411 b: Determine target-velocity-related information corresponding tothe target Doppler measurement information.

S1412 b: Determine the first part and/or the action according to thetarget-velocity-related information and the reference information.

As described above, the target Doppler measurement information may be,such as, an LDF, an LDV, and an ultrasonic Doppler frequency shift, andcomprises a series of envelope wave signals. Correspondingfrequency-domain signals may be obtained by performing, for example, afast Fourier transformation on the envelope wave signals. A Dopplerfrequency component in the frequency-domain signal is proportionate to ablood-flow speed, and therefore a blood-flow speed may be obtained, anda blood-flow flux may further be determined according to the blood-flowspeed and the number of blood cells comprised in a cross section ofblood.

A data type of the target-velocity-related information may be theblood-flow speed, and may also be the blood-flow flux. That is, thetarget-velocity-related information may be target-blood-flow-speedinformation or target-blood-flow-flux information. Because the targetDoppler measurement information comprises a noise caused by the action,the target-velocity-related information also comprises the noise.Specifically, the noise comprises a detection error caused by a changein a blood-flow speed, which is caused by a motion, and a change in thecontact between a detection device of the target Doppler measurementinformation and the limb (different actions cause the contact betweenthe detection device and the limb to change differently). In a commonLDF detection process, people generally try to avoid such a noise.However, in the present application, recognition of the action isimplemented by using such a noise.

In an implementation manner, the step S1412 b may further comprise:

S14121 b: Determine target difference information according to thetarget-velocity-related information and the reference information.

S14122 b: Determine the first part and/or the action at least accordingto the target difference information.

In the step S14121 b, the reference information may be of differenttypes. For example, in an implementation manner, the referenceinformation is reference-velocity-related information corresponding toreference Doppler measurement information acquired, in a case in whichthe first part does not execute the action, from an acquisition part ofthe target Doppler measurement information. Similar to thetarget-velocity-related information, the reference-velocity-relatedinformation may also be the blood-flow speed or the blood-flow flux. Ina case in which the reference-velocity-related information is theblood-flow flux, a waveform thereof may be as shown in FIG. 15. It maybe seen that, the blood-flow flux has an obviously cyclical regularity.Information such as a heart rate and a pulse may be obtained accordingto the waveform.

Correspondingly, the step S14121 b may further comprise:

S141211 b: Divide the target-velocity-related information into multiplepieces of sub-target-velocity-related information according to a cycle.

S141212 b: Respectively perform a cross-correlation calculation on themultiple pieces of sub-target-velocity-related information and thereference information, and determine the target difference informationaccording to a calculation result.

In the step S141211 b, in a case in which an index finger clicks, anobtained waveform of the target-velocity-related information is as shownin FIG. 16. Five pieces of sub-target-velocity-related information C1,C2, C3, C4, and C5 may be obtained by cycle division. The cycle is thesame as a cycle of the reference-velocity-related information.

In the step S141212 b, the reference information may be a waveformbetween two wave crests as shown in FIG. 15. After a cross-correlationcalculation is respectively performed on the reference information andthe 5 pieces of sub-target-velocity-related information, it may be foundthat, a result of a cross-correlation calculation on the referenceinformation and C3 is obviously less than results of cross-correlationcalculations on the reference information and the other pieces ofsub-target-velocity-related information. According to this, it may bedetermined that sub-target-velocity-related information corresponding toC3 is the target difference information.

In an actual application, results of cross-correlation calculations ofthe reference information and each piece of sub-target-velocity-relatedinformation may be compared with a threshold, and if a result is lessthan the threshold, it is determined that a piece of correspondingsub-target-velocity-related information is target differenceinformation. The threshold may be, for example, set to 80% of a resultof a cross-correlation calculation of the reference information withitself.

In another implementation manner, the reference information may be afirst threshold. The first threshold may be set according to anamplitude value of the reference-velocity-related information, forexample, the first threshold is set to a minimum amplitude value or amaximum amplitude value of the reference-velocity-related information.

Correspondingly, the step S14121 b may further comprise:

S14121 b′: Compare an amplitude value that is in thetarget-velocity-related information and a value of the referenceinformation, and determine the target difference information accordingto a comparison result.

FIG. 17 is used as an example. FIG. 17 shows a waveform of thetarget-velocity-related information in a case in which a middle fingerof the user executes a click action, where the waveform within a circleis obviously different from a waveform outside the circle. The waveformwithin the circle is a waveform affected by the click action, that is, awaveform corresponding to the target difference information. Thereference information, for example, may be set to a minimum amplitudevalue of the reference-velocity-related information, for example, thereference information is set to 450, and then, the amplitude value inthe target-velocity-related information is compared with the amplitudevalue. It may be seen that, an amplitude value of the waveform withinthe circle is less than the value of the reference information, andtherefore it may be determined that the target difference information isthe waveform within the circle.

It is understood by a person skilled in the art that, the foregoing twomanners for determining the target difference information may further beused together, to improve accuracy and efficiency.

In the step S14122 b, the first part and/or the action is determined atleast according to the target difference information. In animplementation manner, the step S14122 b may comprise:

S141221 b: Respectively calculate the similarity between a waveform ofthe target difference information and at least one known waveform, anddetermine a target known waveform according to a calculation result.

S141222 b: Determine the first part and/or the action according to thetarget known waveform.

The at least one known waveform may be a set of multiple known waveformsand may be obtained by pre-training, for example, the user makes thefirst part execute different actions in advance and correspondinglyacquires waveforms of corresponding target difference information as theknown waveforms. Therefore, correspondences among the first part, theaction, and the known waveform may be established. The correspondencesmay be as shown in Table 1.

In an actual application, in the step S141221 b, the similarity of awaveform of the target difference information and each known waveform inthe set may be respectively calculated, and then a known waveform of thehighest similarity is selected as the target known waveform. Further, inthe step S141222 b, the first part and/or the action may be determinedaccording to the target known waveform.

A first row in Table 1 is used as an example. It is assumed that awaveform of the target difference information is the waveform within acircle as shown in FIG. 16, and it may be obtained by calculation thatthe waveform of the target difference information is most similar to aknown waveform A, and therefore it may be determined that the targetknown waveform is the known waveform A, and it may further be determinedthat the first part is an index finger, and an action is click.

In another implementation manner, the step S14122 b may be further asfollows:

S14122 b′: Determine the action according to the number of wave troughsor wave crests comprised in the target difference information.

The number of wave troughs or wave crests comprised in the targetdifference information is the same as the number of times that theaction is executed. As shown in FIG. 17, in a case in which a middlefinger clicks, the corresponding number of wave troughs is 1. As shownin FIG. 16, in a case in which an index finger clicks, the correspondingnumber of wave troughs or wave crests is 1. In addition, FIG. 18 is awaveform of target-velocity-related information, which is obtained in acase in which an index finger double-clicks. The waveform within acircle is corresponding to the target difference information. It may beseen that, in this case, the number of wave troughs or wave crestscomprised in the target difference information is 2.

In another implementation manner, the step S14122 b may be further asfollows:

S14122 b″: Determine the action according to a cycle corresponding tothe target difference information.

The cycle corresponding to the target difference information iscorresponding to a cycle in which the first part executes the action.That is, the longer the first part executes the action each time, thelonger the cycle of the target difference information is. Therefore, thecycle corresponding to the target difference information may reflect anexecution speed of the action, and therefore the action may bedetermined. For example, the first part is a foot. If a cycle of anaction of raising and putting down the foot is 0.3 s, it may bedetermined that a corresponding action is walking; and if a cycle of anaction of raising and putting down the foot is 0.03 s, it may bedetermined that a corresponding action is running. Certainly, in a casein which the first part is a hand, it may also be determined whether auser walks or runs according to a cycle of forward and backward swingingof the hand.

In the step S142 b, the input information is determined according to thefirst part and/or the action.

Correspondences between the first part and/or the action and the inputinformation may be predetermined, and the correspondences may be asshown in FIG. 2. A correspondence table as shown in Table 2 may bepre-stored in a wearable device, such as a smart bracelet, and moreover,such a correspondence table may be provided in an operating instructionof the wearable device, so as to instruct and train a user to performcorresponding command inputting by means of an action similar to anaction in Table 2.

In addition, referring to FIG. 19, in another implementation manner, thestep S140 b may comprise:

S141 b′: Determine a signal feature of the target Doppler measurementinformation.

S142 b′: Determine the input information according to the signal featureand the reference information.

In the step S141 b′, the signal feature of the target Dopplermeasurement information comprises at least one of a fingerprint, anaverage value, and a difference of the target Doppler measurementinformation. The fingerprint is formed of at least one of an amplitude,a phase, and a spectrum of the target Doppler measurement information;the average value is an average value of at least one of the amplitude,the phase, and the spectrum of the target Doppler measurementinformation; and the difference is a difference of at least one of theamplitude, the phase, and the spectrum of the target Doppler measurementinformation.

In the step S142 b′, the reference information may be a reference signalfeature obtained by pre-training, for example, in a training stage,corresponding actions may be executed according to Table 2, andcorrespondingly, signal features of corresponding Doppler measurementinformation may be acquired as the reference information. In a specificapplication, the similarities between the signal feature of the targetDoppler measurement information and multiple pieces of referenceinformation may be obtained by calculation, and input informationcorresponding to one piece of reference information having the highestsimilarity is used as the input information.

In an implementation manner, the method may further comprise:

S150: Input the input information.

For example, according to a determining result indicating that the inputinformation is a sleep command, the sleep command is input to a devicesuch as a bracelet or a mobile phone, and the device may switch to asleep mode according to the sleep command. A device corresponding to theinput information may be preset, and certainly, may also be designatedby means of the input information.

In addition, the embodiments of the present application further providea computer readable medium, comprising computer readable instructionsfor being executed to perform the following operations: operations ofsteps S120 and S140 in the method in the implementation manner as shownin FIG. 1 are performed.

In conclusion, according to the method in the embodiments of the presentapplication, a body of a user may be used as an input interface to inputinformation to a corresponding electronic device, thereby improving aninput capability of a wearable device and the like and improving userexperience.

FIG. 20 is a schematic structural diagram of modules of a device fordetermining input information according to an embodiment of the presentapplication. The device for determining input information may bedisposed in a wearable device such as a smart wristband or a smart watchas a functional module, and certainly, may also be used by a user as anindependent wearable device. As shown in FIG. 20, the device 2000 maycomprise:

an acquiring module 2010, configured to acquire target blood-flowinformation about a first part of a body of a user or a second part thatcorresponds to the first part in response to the first part executing anaction; and

a determining module 2020, configured to determine input informationaccording to the target blood-flow information and referenceinformation.

According to the device in some embodiments of the present application,an action is executed in response to a first part of a body of a user,and target blood-flow information about the first part or a second partthat corresponds to the first part is acquired; and input information isdetermined according to the target blood-flow information and referenceinformation, thereby affecting the target blood-flow information bymeans of a body action of a user, and moreover, the input information isdetermined according to the target blood-flow information. The body ofthe user is used as an input interface, to cause an interaction area tobe increased, which helps to improve input efficiency and userexperience.

The following describes functions of the acquiring module 2010 and thedetermining module 2020 in detail with reference to the specificimplementation manners.

The acquiring module 2010 is configured to acquire target blood-flowinformation about a first part of a body of a user or a second part thatcorresponds to the first part, in response to the first part executingan action.

The first part, that is, an action part, for example, may be a finger, apalm, a wrist, a neck, a foot, a leg, and the like of a user. Inaddition to being used as the action part, the first part may also beused as an acquisition part for target blood-flow information at thesame time, for example, in a case in which an acquiring sensor for thetarget blood-flow information is a smart bracelet, the wrist may be usedas the action part and the acquisition part simultaneously.

The second part is another optional acquisition part for the targetblood-flow information. Moreover, the second part is a part adjacent tothe first part. That is, a distance between the first part and thesecond part should be less than a distance threshold, for example, thedistance is less than 0.1 m. Moreover, it is found by the inventor inthe research process that, a shorter distance between the first part andthe second part leads to a smaller error of the method. Generally, thefirst part and the second part are located at a same limb of the user.For example, in a case in which a finger is used as the action part, thewrist on the same limb may be used as an acquisition part.

The actions may be some common actions in daily life, such as, a fingerclicks, a hand makes a fist, and a palm is stretched out, and may alsobe some training actions, such as a finger double-clicks fast.

As described above, the blood-flow information may be PPG information orDoppler measurement information. Correspondingly, the target blood-flowinformation may be target PPG information or target Doppler measurementinformation.

The determining module 2020 is configured to determine input informationaccording to the target blood-flow information and referenceinformation.

a) In an implementation manner, the target blood-flow information istarget PPG information. Correspondingly, the determining module 2020 isconfigured to determine input information according to the target PPGinformation and reference information.

In an implementation manner, a first correspondence between the targetPPG information and the input information may be directly established,and therefore the input information may be directly determined accordingto the target PPG information in combination with the referenceinformation.

In another implementation manner, referring to FIG. 21, the determiningmodule 2020 may comprise:

a first determining submodule 2021 a, configured to determine the firstpart and/or the action according to the target PPG information and thereference information; and

a second determining submodule 2022 a, configured to determine the inputinformation according to the first part and/or the action.

In an implementation manner, referring to FIG. 22, the first determiningsubmodule 2021 a comprises:

a first determining unit 20211 a, configured to determine targetdifference information according to the target PPG information and thereference information; and

a second determining unit 20212 a, configured to determine the firstpart and/or the action at least according to the target differenceinformation.

In an implementation manner, the reference information may be a firstthreshold. The first threshold may be set according to PPG informationacquired, in a case in which the first part does not execute the action,that is, the first part remains static, from an acquisition part of thetarget PPG information (PPG information acquired in a normal case forshort below), for example, the first threshold is set to a minimumamplitude value of PPG information acquired in a normal case, or amaximum amplitude value of PPG information acquired in a normal case.

The target difference information is a part of the target PPGinformation, and the action causes the part of the information to beobviously different from the PPG information acquired in a normal case.For example, in a case in which a middle finger clicks, an obtainedwaveform of the target PPG information is as shown in FIG. 7, where thepart, which is within the circle, of the waveform is obviously differentfrom the waveform outside the circle. The part, which is within thecircle, of the waveform is a waveform corresponding to the targetdifference information. The waveform is a waveform formed due to achange in a normal PPG waveform, which is caused by a click performed bythe middle finger. It may be seen that, a minimum amplitude value of thepart, which is within the circle, of the waveform is obviously lowerthan an amplitude value of the PPG information acquired in a normalcase.

Therefore, in an implementation manner, the first determining unit 20211a is configured to compare an amplitude value that is in the target PPGinformation and a value of the reference information, and determine thetarget difference information according to a comparison result.

Specifically, in a case in which the reference information is a minimumamplitude value of PPG information acquired in a normal case, a part,whose amplitude value is less than the value of the referenceinformation, of the target PPG information may be determined as thetarget difference information. Certainly, in a case in which thereference information is a maximum amplitude value of PPG informationacquired in a normal case, a part, whose amplitude value is greater thanthe value of the reference information, of the target PPG informationmay be determined as the target difference information. FIG. 8 is usedas an example. FIG. 8 shows a waveform of target PPG informationobtained at a wrist in a case in which a fist is made, where thewaveform within a circle formed of a solid line is obviously differentfrom the waveform outside the circle formed of the solid line. Thewaveform within the circle formed of the solid line is a waveformcorresponding to the target difference information. The waveform is awaveform formed due to a change in a normal PPG waveform, which iscaused by the fist making. It may be seen that, a maximum amplitudevalue of the waveform within the circle formed of the solid line isobviously higher than an amplitude value of the PPG information acquiredin a normal case.

In another implementation manner, the reference information may bereference PPG information acquired from an acquisition part of thetarget PPG information in a case in which the first part does notexecute the action, that is, the reference information is PPGinformation acquired in a normal case. A waveform of the reference PPGinformation may be as shown in FIG. 3 and may be acquired in advance.

Correspondingly, referring to FIG. 23, in an implementation manner, thefirst determining unit 20211 a comprises:

a division subunit 202111 a, configured to divide the target PPGinformation into multiple pieces of sub target PPG information accordingto a cycle; and

a determining subunit 202112 a, configured to respectively perform across-correlation calculation on the multiple pieces of sub target PPGinformation and the reference information, and determine the targetdifference information according to a calculation result.

The waveform shown in FIG. 7 is still used as an example. The divisionsubunit 202111 a may divide the waveform shown in FIG. 7 into C1, C2,C3, C4, and C5 by taking two adjacent wave crests as a cycle. There arefive subwaveforms in total. The five subwaveforms are corresponding tofive pieces of sub target PPG information. A waveform at edges may beignored. This is because some extra pieces of PPG information may beacquired during acquiring of the target PPG information.

In the determining subunit 202112 a, the reference information may be aPPG waveform between two wave crests, which is acquired in a normalcase. After a cross-correlation calculation is respectively performed onthe five pieces of sub target PPG information and the referenceinformation, it may be found that, a result of a cross-correlationcalculation on the reference information and C2 is obviously less thanresults of cross-correlation calculations on the reference informationand the other pieces of sub target PPG information. According to this,it may be determined that PPG information corresponding to C2 is thetarget difference information.

In an actual application, results of cross-correlation calculations ofthe reference information and each piece of sub target PPG informationmay be compared with a threshold, and if a result is less than thethreshold, it is determined that a piece of corresponding sub target PPGinformation is target difference information. The threshold may be, forexample, set to 80% of a result of a cross-correlation calculation ofthe reference information and itself.

It is understood by a person skilled in the art that, the foregoing twomanners for determining the target difference information may further beused together, to improve accuracy and efficiency.

In an implementation manner, the second determining unit 20212 a isconfigured to determine the action according to the number of wavetroughs or wave crests comprised in the target difference information.

The number of wave troughs or wave crests comprised in the targetdifference information is the same as the number of times that theaction is executed. As shown in FIG. 7, in a case in which a middlefinger clicks, the corresponding number of wave troughs is 1. As shownin FIG. 8, in a case in which a fist is made once, the correspondingnumber of wave troughs or wave crests is 1. In addition, FIG. 10 is awaveform of target PPG information, which is obtained in a case in whichan index finger clicks. The waveform within a circle is corresponding tothe target difference information, and the corresponding number of wavetroughs or wave crests of the target difference information is also 1.FIG. 11 is a waveform of target PPG information, which is obtained in acase in which an index finger double-clicks. The waveform within acircle is corresponding to the target difference information. It may beseen that, in this case, the number of wave troughs or wave crestscomprised in the target difference information is 2.

In another implementation manner, the second determining unit 20212 a isconfigured to determine the action according to a cycle corresponding tothe target difference information.

The cycle corresponding to the target difference information iscorresponding to a cycle in which the first part executes the action.That is, the longer the first part executes the action each time, thelonger the cycle of the target difference information is. Therefore, thecycle corresponding to the target difference information may reflect anexecution speed of the action, and therefore the action may bedetermined. For example, the first part is a foot. If a cycle of anaction of raising and putting down the foot is 0.3 s, it may bedetermined that a corresponding action is walking; and if a cycle of anaction of raising and putting down the foot is 0.03 s, it may bedetermined that a corresponding action is running. Certainly, in a casein which the first part is a hand, it may also be determined whether auser walks or runs according to a cycle of forward and backward swingingof the hand.

In another implementation manner, referring to FIG. 24, the seconddetermining unit 20212 a comprises:

a first determining subunit 202121 a, configured to respectivelycalculate the similarity between a waveform of the target differenceinformation and at least one known waveform, and determine a targetknown waveform according to a calculation result; and

a second determining subunit 202122 a, configured to determine the firstpart and/or the action according to the target known waveform.

The at least one known waveform may be a set of multiple known waveformsand may be obtained by pre-training, for example, the user makes thefirst part execute different actions in advance and correspondinglyacquires waveforms of corresponding target difference information as theknown waveforms. Therefore, correspondences among the first part, theaction, and the known waveform may be established. The correspondencesmay be as shown in Table 1.

In an actual application, the similarity of a waveform of the targetdifference information and each known waveform in the set may berespectively calculated, and then a known waveform of the highestsimilarity is selected as the target known waveform. Further, the firstpart and/or the action may be determined according to the target knownwaveform.

The second determining submodule 2022 a is configured to determine theinput information according to the first part and/or the action.

Correspondences between the first part and/or the action and the inputinformation may be predetermined, and the correspondences may be asshown in FIG. 2. A second row is used as an example. It is assumed thata smart bracelet is in communication with smart glasses, the smartbracelet acquires an action instruction of a user and controls the smartglasses, and in a case in which the smart bracelet recognizes an actionthat an index finger double-clicks, the smart bracelet may control thesmart glasses to enable an APP currently presented to the user, forexample, enable a camera function. A correspondence table as shown inTable 2 may be pre-stored in a wearable device, such as a smartbracelet, and moreover, such a correspondence table may be provided inan operating instruction of the wearable device, so as to instruct andtrain a user to perform corresponding command inputting by means of anaction similar to an action in Table 2.

In addition, referring to FIG. 25, in an implementation manner, thedetermining module 2020 comprises:

a third determining submodule 2023 a, configured to determine a signalfeature of the target PPG information; and

a fourth determining submodule 2024 a, configured to determine the inputinformation according to the signal feature and the referenceinformation.

The signal feature of the target PPG information comprises at least oneof a fingerprint, an average value, and a difference of the target PPGinformation. The fingerprint is formed of at least one of an amplitude,a phase, and a spectrum of the target PPG information; the average valueis an average value of at least one of the amplitude, the phase, and thespectrum of the target PPG information; and the difference is adifference of at least one of the amplitude, the phase, and the spectrumof the target PPG information.

The reference information may be a reference signal feature obtained bypre-training, for example, in a training stage, corresponding actionsmay be executed according to Table 2, and correspondingly, signalfeatures of corresponding PPG information may be acquired as thereference information. In a specific application, the similaritiesbetween the signal feature of the target PPG information and multiplepieces of reference information may be obtained by calculation, andinput information corresponding to one piece reference informationhaving the highest similarity is used as the input information.

b) In another implementation manner, the target blood-flow informationis target Doppler measurement information. Correspondingly, thedetermining module 2020 is configured to determine input informationaccording to the target Doppler measurement information and referenceinformation.

In an implementation manner, referring to FIG. 26, the determiningmodule 2020 comprises:

a first determining submodule 2021 b, configured to determine the firstpart and/or the action according to the target Doppler measurementinformation and the reference information; and

a second determining submodule 2022 b, configured to determine the inputinformation according to the first part and/or the action.

In an implementation manner, referring to FIG. 27, the first determiningsubmodule 2021 b comprises:

a first unit 20211 b, configured to determine target-velocity-relatedinformation corresponding to the target Doppler measurement information;and

a second unit 20212 b, configured to determine the first part and/or theaction according to the target-velocity-related information and thereference information.

A data type of the target-velocity-related information may be theblood-flow speed, and may also be the blood-flow flux. That is, thetarget-velocity-related information may be target-blood-flow-speedinformation or target-blood-flow-flux information. Because the targetDoppler measurement information comprises a noise caused by the action,the target-velocity-related information also comprises the noise.Specifically, the noise comprises a detection error caused by a changein a blood-flow speed, which is caused by a motion, and a change in thecontact between a detection device of the target Doppler measurementinformation and the limb. In a common LDF detection process, peoplegenerally try to avoid such a noise. However, in the presentapplication, recognition of the action is implemented by using such anoise.

In an implementation manner, referring to FIG. 28, the second unit 20212b comprises:

a first determining subunit 202121 b, configured to determine targetdifference information according to the target-velocity-relatedinformation and the reference information; and

a second determining subunit 202122 b, configured to determine the firstpart and/or the action at least according to the target differenceinformation.

The reference information may be of different types. For example, in animplementation manner, the reference information isreference-velocity-related information corresponding to referenceDoppler measurement information acquired, in a case in which the firstpart does not execute the action, from an acquisition part of the targetDoppler measurement information. Similar to the target-velocity-relatedinformation, the reference-velocity-related information may also be theblood-flow speed or the blood-flow flux. In a case in which thereference-velocity-related information is the blood-flow flux, awaveform thereof may be as shown in FIG. 15. It may be seen that, theblood-flow flux has an obviously cyclical regularity. Information suchas a heart rate and a pulse may be obtained according to the waveform.

Correspondingly, in an implementation manner, referring to FIG. 29, thefirst determining subunit 202121 b comprises:

a first-second-level subunit 2021211 b, configured to divide thetarget-velocity-related information into multiple pieces ofsub-target-velocity-related information according to a cycle; and

a second-second-level subunit 2021212 b, configured to respectivelyperform a cross-correlation calculation on the multiple pieces ofsub-target-velocity-related information and the reference information,and determine the target difference information according to acalculation result.

For example, in a case in which an index finger clicks, an obtainedwaveform of the target-velocity-related information is as shown in FIG.16. Five pieces of sub-target-velocity-related information C1, C2, C3,C4, and C5 may be obtained by dividing, according to the cycle, thewaveform. The cycle is the same as a cycle of thereference-velocity-related information.

The reference information may be a waveform between two wave crests asshown in FIG. 15. After a cross-correlation calculation is respectivelyperformed on the reference information and the five pieces ofsub-target-velocity-related information, it may be found that, a resultof a cross-correlation calculation on the reference information and C3is obviously less than results of cross-correlation calculations on thereference information and the other pieces ofsub-target-velocity-related information. According to this, it may bedetermined that sub-target-velocity-related information corresponding toC3 is the target difference information.

In an actual application, results of cross-correlation calculations ofthe reference information and each piece of sub-target-velocity-relatedinformation may be compared with a threshold, and if a result is lessthan the threshold, it is determined that a piece of correspondingsub-target-velocity-related information is target differenceinformation. The threshold may be, for example, set to 80% of a resultof a cross-correlation calculation of the reference information anditself.

In another implementation manner, the reference information may be afirst threshold. The first threshold may be set according to anamplitude value of the reference-velocity-related information, forexample, the first threshold is set to a minimum amplitude value or amaximum amplitude value of the reference-velocity-related information.

Correspondingly, the first determining subunit 202121 b is configured tocompare an amplitude value that is in the target-velocity-relatedinformation and a value of the reference information, and determine thetarget difference information according to a comparison result.

FIG. 17 is used as an example. FIG. 17 shows a waveform of thetarget-velocity-related information in a case in which a middle fingerof the user executes a click action, where the waveform within a circleis obviously different from a waveform outside the circle. The waveformwithin the circle is a waveform affected by the click action, that is, awaveform corresponding to the target difference information. Thereference information, for example, may be set to a minimum amplitudevalue of the reference-velocity-related information, for example, thereference information is set to 450, and then, the amplitude value inthe target-velocity-related information is compared with the amplitudevalue. It may be seen that, an amplitude value of the waveform withinthe circle is less than the value of the reference information, andtherefore it may be determined that the target difference information isthe waveform within the circle.

It is understood by a person skilled in the art that, the foregoing twomanners for determining the target difference information may further beused together, to improve accuracy and efficiency.

The second determining subunit 202122 b is configured to determine thefirst part and/or the action at least according to the target differenceinformation.

In an implementation manner, referring to FIG. 30, the seconddetermining subunit 202122 b comprises:

a third-second-level subunit 2021221 b, configured to respectivelycalculate the similarity between a waveform of the target differenceinformation and at least one known waveform, and determine a targetknown waveform according to a calculation result;

and a fourth-second-level subunit 2021222 b, configured to determine thefirst part and/or the action according to the target known waveform.

The at least one known waveform may be a set of multiple known waveformsand may be obtained by pre-training, for example, the user makes thefirst part execute different actions in advance and correspondinglyacquires waveforms of corresponding target difference information as theknown waveforms. Therefore, correspondences among the first part, theaction, and the known waveform may be established. The correspondencesmay be as shown in Table 1.

In an actual application, the similarity of a waveform of the targetdifference information and each known waveform in the set may berespectively calculated, and then a known waveform of the highestsimilarity is selected as the target known waveform. Further, the firstpart and/or the action may be determined according to the target knownwaveform.

A first row in Table 1 is used as an example. It is assumed that awaveform of the target difference information is the waveform within acircle as shown in FIG. 16, and it may be obtained by calculation thatthe waveform of the target difference information is most similar to aknown waveform A, and therefore it may be determined that the targetknown waveform is the known waveform A, and it may further be determinedthat the first part is an index finger, and an action is click.

In another implementation manner, the second determining subunit 202122b is configured to determine the action according to the number of wavetroughs or wave crests comprised in the target difference information.

The number of wave troughs or wave crests comprised in the targetdifference information is the same as the number of times that theaction is executed. As shown in FIG. 17, in a case in which a middlefinger clicks, the corresponding number of wave troughs is 1. As shownin FIG. 16, in a case in which an index finger clicks, the correspondingnumber of wave troughs or wave crests is 1. In addition, FIG. 18 is awaveform of target-velocity-related information, which is obtained in acase in which an index finger double-clicks. The waveform within acircle is corresponding to the target difference information. It may beseen that, in this case, the number of wave troughs or wave crestscomprised in the target difference information is 2.

In another implementation manner, the second determining subunit 202122b is configured to determine the action according to a cyclecorresponding to the target difference information.

The cycle corresponding to the target difference information iscorresponding to a cycle in which the first part executes the action.That is, the longer the first part executes the action each time, thelonger the cycle of the target difference information is. Therefore, thecycle corresponding to the target difference information may reflect anexecution speed of the action, and therefore the action may bedetermined. For example, the first part is a foot. If a cycle of anaction of raising and putting down the foot is 0.3 s, it may bedetermined that a corresponding action is walking; and if a cycle of anaction of raising and putting down the foot is 0.03 s, it may bedetermined that a corresponding action is running. Certainly, in a casein which the first part is a hand, it may also be determined whether auser walks or runs according to a cycle of forward and backward swingingof the hand.

The second determining submodule 2022 b is configured to determine theinput information according to the first part and/or the action.

Correspondences between the first part and/or the action and the inputinformation may be predetermined, and the correspondences may be asshown in FIG. 2. A correspondence table as shown in Table 2 may bepre-stored in a wearable device, such as a smart bracelet, and moreover,such a correspondence table may be provided in an operating instructionof the wearable device, so as to instruct and train a user to performcorresponding command inputting by means of an action similar to anaction in Table 2.

In addition, referring to FIG. 31, in an implementation manner, thedetermining module 2020 comprises:

a third determining submodule 2023 b, configured to determine a signalfeature of the target Doppler measurement information; and

a fourth determining submodule 2024 b, configured to determine the inputinformation according to the signal feature and the referenceinformation.

The signal feature of the target Doppler measurement informationcomprises at least one of a fingerprint, an average value, and adifference of the target Doppler measurement information. Thefingerprint is formed of at least one of an amplitude, a phase, and aspectrum of the target Doppler measurement information; the averagevalue is an average value of at least one of the amplitude, the phase,and the spectrum of the target Doppler measurement information; and thedifference is a difference of at least one of the amplitude, the phase,and the spectrum of the target Doppler measurement information.

The reference information may be a reference signal feature obtained bypre-training, for example, in a training stage, corresponding actionsmay be executed according to Table 2, and correspondingly, signalfeatures of corresponding Doppler measurement information may beacquired as the reference information. In a specific application, thesimilarities between the signal feature of the target Dopplermeasurement information and multiple pieces of reference information maybe obtained by calculation, and input information corresponding to onepiece reference information having the highest similarity is used as theinput information.

An application scenario of the method and device for determining inputinformation according to the embodiments of the present application maybe as follows: A left wrist of a user wears a smart bracelet; when theuser wants to know current time, the user quickly clicks a desktop twiceby using an index finger of a left hand, the bracelet recognizes thatthe index finger of the left hand of the user executes a double-clickaction by detecting a change in blood-flow information about the leftwrist, and determines that corresponding input information is atime-displayed command, and therefore, the command is input to a controlmodule, and the control module inputs the current time in a voice mannerby controlling the bracelet; and when the user wants the bracelet tosleep, the user quickly clicks a desktop type by using a middle fingerof a left hand, the bracelet recognizes that the middle finger of theleft hand executes a double-click action by detecting a change inblood-flow information about a left wrist, and determines thatcorresponding input information is a sleep command, and therefore, thecommand is input to the control module, and the control module controlsthe bracelet to switch to a sleep mode.

A hardware structure of a device for determining input informationaccording to another embodiment of the present application is as shownin FIG. 32. Specific implementation of the device for determining inputinformation is not limited in a specific embodiment of the presentapplication. Referring to FIG. 32, the device 3200 may comprise:

a processor 3210, a communications interface 3220, a memory 3230, and acommunications bus 3240.

The processor 3210, the communications interface 3220, and the memory3230 communicate with each other through the communications bus 3240.

The communications interface 3220 is configured to communicate withanother network element.

The processor 3210 is configured to execute a program 3232, andspecifically, may execute a related step in the embodiments of themethod shown in FIG. 1.

Specifically, the program 3232 may comprise program code. The programcode comprises computer operation instructions.

The processor 3210 may be a central processing unit (CPU) or anapplication specific integrated circuit (ASIC), or may be configured asone or more integrated circuits that implement the embodiments of thepresent application.

The memory 3230 is configured to store the program 3232. The memory 3230may comprise a random access memory (RAM), and may also comprise anon-volatile memory, for example, at least one magnetic disk storage.The processor 3232 may specifically execute the following steps:

in response to a first part of a body of a user executing an action,target blood-flow information about the first part or a second part thatcorresponds to the first part is acquired; and

input information is determined according to the target blood-flowinformation and reference information.

Reference can be made to corresponding steps or modules in theembodiments for specific implementation of the steps in the program3232, which is not repeated herein. A person skilled in the art mayclearly understand that, reference can be made to the correspondingprocess description in the method embodiments for the device describedabove and the specific working procedures of the modules, and will notbe repeated herein in order to make the description convenient andconcise.

It can be appreciated by a person of ordinary skill in the art that,exemplary units and method steps described with reference to theembodiments disclosed in this specification can be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether these functions are executed by hardware or softwaredepends on specific applications and design constraints of the technicalsolution. A person skilled in the art may use different methods toimplement the described functions for each specific application, butsuch implementation should not be construed as a departure from thescope of the present application.

If the function is implemented in the form of a software functional unitand is sold or used as an independent product, the product can be storedin a non-transitory computer-readable storage medium. Based on suchunderstanding, the technical solution of the present applicationessentially, or the part that contributes to the prior art, or a part ofthe technical solution may be embodied in the form of a softwareproduct; the computer software product is stored in a storage medium andcomprises several instructions for enabling a computer device (which maybe a personal computer, a server, a network device, or the like) toexecute all or some of the steps of the method in the embodiments of thepresent application. The foregoing storage medium comprises variousmediums capable of storing program code, such as, a USB flash drive, aremovable hard disk, a read-only memory (ROM), a random access memory(RAM), a magnetic disk, or an optical disc.

The foregoing implementation manners are only used to describe thepresent application, but not to limit the present application. A personof ordinary skill in the art can still make various alterations andmodifications without departing from the spirit and scope of the presentapplication; therefore, all equivalent technical solutions also fallwithin the scope of the present application, and the patent protectionscope of the present application should be subject to the claims.

What is claimed is:
 1. A method for determining input information,comprising: in response to detecting a motion of a first part of a bodyof a user, acquiring target photoelectric plethysmography (PPG)information about the first part or a second part that corresponds tothe first part; determining target difference information according tothe target PPG information and reference information; determining thefirst part and/or an action executed by the user at least according tothe target difference information; and determining the input informationaccording to the first part and/or the action.
 2. The method of claim 1,wherein the determining target difference information according to thetarget PPG information and the reference information comprises: dividingthe target PPG information into multiple pieces of sub target PPGinformation according to a cycle; and respectively performing across-correlation calculation on the multiple pieces of sub target PPGinformation and the reference information, and determining the targetdifference information according to a calculation result.
 3. The methodof claim 2, wherein the reference information is reference PPGinformation acquired, in a case in which the first part does not executethe action, from an acquisition part of the target PPG information. 4.The method of claim 1, wherein the determining target differenceinformation according to the target PPG information and the referenceinformation comprises: comparing an amplitude value that is in thetarget PPG information and a value of the reference information, anddetermining the target difference information according to a comparisonresult.
 5. The method of claim 4, wherein the reference information is afirst threshold.
 6. The method of claim 1, wherein the determining thefirst part and/or the action at least according to the target differenceinformation comprises: respectively calculating the similarity between awaveform of the target difference information and at least one knownwaveform, and determining a target known waveform according to acalculation result; and determining the first part and/or the actionaccording to the target known waveform.
 7. The method of claim 1,wherein the determining the first part and/or the action at leastaccording to the target difference information comprises: determiningthe action according to the number of wave troughs or wave crestscomprised in the target difference information.
 8. The method of claim1, wherein the determining the first part and/or the action at leastaccording to the target difference information comprises: determiningthe action according to a cycle corresponding to the target differenceinformation.
 9. The method of claim 1, wherein the determining inputinformation according to the target PPG information and referenceinformation comprises: determining a signal feature of the target PPGinformation; and determining the input information according to thesignal feature and the reference information.
 10. The method of claim 1,wherein the first part is a hand or a wrist of the user.
 11. A devicefor determining input information, comprising a processor and a memorystoring computer executable instructions that, when executed by theprocessor, cause the device to execute operations, comprising: inresponse to detecting a motion of a first part of a body of a user,acquiring target photoelectric plethysmography (PPG) information aboutthe first part or a second part that corresponds to the first part;determining target difference information according to the target PPGinformation and reference information; determining the first part and/oran action executed by the user at least according to the targetdifference information; and determining the input information accordingto the first part and/or the action.
 12. The device of claim 11, whereinthe operations further comprise: dividing the target PPG informationinto multiple pieces of sub target PPG information according to a cycle;and performing a cross-correlation calculation on the multiple pieces ofsub target PPG information and the reference information, anddetermining the target difference information according to a calculationresult.
 13. The device of claim 11, wherein the operations furthercomprise: comparing an amplitude value that is in the target PPGinformation and a value of the reference information, and determiningthe target difference information according to a comparison result. 14.The device of claim 11, wherein the operations further comprise:respectively calculating the similarity between a waveform of the targetdifference information and at least one known waveform, and determininga target known waveform according to a calculation result; anddetermining the first part and/or the action according to the targetknown waveform.
 15. The device of claim 11, wherein the operationsfurther comprise: determining the action according to the number of wavetroughs or wave crests comprised in the target difference information.16. The device of claim 11, wherein the operations further comprise:determining the action according to a cycle corresponding to the targetdifference information.
 17. The device of claim 11, wherein theoperations further comprise: determining a signal feature of the targetPPG information; and determining the input information according to thesignal feature and the reference information.
 18. A device fordetermining input information, comprising: an acquiring module,configured to acquire target photoelectric plethysmography (PPG)information about a first part of a body of a user or a second part thatcorresponds to the first part, in response to detecting a motion of thefirst part; and a determining module, configured to determine the inputinformation by: determining target difference information according tothe target PPG information and reference information; determining thefirst part and/or an action executed by the user at least according tothe target difference information; and determining the input informationaccording to the first part and/or the action.
 19. A method fordetermining input information, comprising: in response to detecting amotion of a first part of a body of a user, acquiring target blood-flowinformation about the first part or a second part that corresponds tothe first part; determining target difference information according tothe target blood-flow information and reference information; determiningthe first part and/or an action executed by the user at least accordingto the target difference information; and determining the inputinformation according to the first part and/or the action.
 20. A devicefor determining input information, comprising: an acquiring module,configured to acquire target blood-flow information about a first partof a body of a user or a second part that corresponds to the first part,in response to detecting a motion of the first part; and a determiningmodule, configured to determine the input information by: determiningtarget difference information according to the target blood-flowinformation and reference information; determining the first part and/oran action executed by the user at least according to the targetdifference information; and determining the input information accordingto the first part and/or the action.
 21. A wearable device, comprising adevice for determining input information, wherein the device fordetermining input information comprises: an acquiring module, configuredto acquire target photoelectric plethysmography (PPG) information abouta first part of a body of a user or a second part that corresponds tothe first part, in response to detecting a motion of the first part; anda determining module, configured to determine the input information by:determining target difference information according to the target PPGinformation and reference information; determining the first part and/oran action executed by the user at least according to the targetdifference information; and determining the input information accordingto the first part and/or the action; or wherein the device fordetermining input information comprises: an acquiring module, configuredto acquire target blood-flow information about a first part of a body ofa user or a second part that corresponds to the first part, in responseto detecting a motion of the first part; and a determining module,configured to determine the input information by: determining targetdifference information according to the target blood-flow informationand reference information; determining the first part and/or an actionexecuted by the user at least according to the target differenceinformation; and determining the input information according to thefirst part and/or the action.
 22. A non-transitory computer readablemedium comprising at least one executable instruction, which, inresponse to execution, causes a processor to perform operationscomprising: in response to detecting a motion of a first part of a bodyof a user, acquiring target photoelectric plethysmography (PPG)information about the first part or a second part that corresponds tothe first part; determining target difference information according tothe target PPG information and reference information; determining thefirst part and/or an action executed by the user at least according tothe target difference information; and determining input informationaccording to the first part and/or the action.
 23. A non-transitorycomputer readable medium comprising at least one executable instruction,which, in response to execution, causes a processor to performoperations comprising: in response to detecting a motion of a first partof a body of a user, acquiring target blood-flow information about thefirst part or a second part that corresponds to the first part;determining target difference information according to the targetblood-flow information and reference information; determining the firstpart and/or an action executed by the user at least according to thetarget difference information; and determining input informationaccording to the first part and/or the action.
 24. A device fordetermining input information comprising a processor and a memorystoring computer executable instructions that, when executed by theprocessor, cause the device to execute operations comprising: inresponse to detecting a motion of a first part of a body of a user,acquiring target blood-flow information about the first part or a secondpart that corresponds to the first part; determining target differenceinformation according to the target blood-flow information and referenceinformation; determining the first part and/or an action executed by theuser at least according to the target difference information; anddetermining the input information according to the first part and/or theaction.